For example, Patent Document 1 discloses a pyroelectric type infrared detection device which includes a case member having two pyroelectric elements therein and two lenses condensing infrared lights into the two pyroelectric elements.
Patent Document 2 discloses a pyroelectric type infrared detection device with a structure where a pyroelectric element is mounted on a circuit board. In a pyroelectric type infrared detection device of Patent Document 2, electrodes of the pyroelectric element and other electrodes of the circuit board are electrically connected by hardened conductive adhesives. Hardness of the hardened conductive adhesive is 5 B to 6 B of pencil hardness. The hardened conductive adhesives used in Patent Document 2 are soft.